The instant invention relates to apparatus used to facilitate the repair of valves utilized in underground water main meters.
In order to account for and bill for water dispensed by large water systems, such as municipal water systems, meters of various sizes are distributed throughout the system. One type of meter utilized is the Hersey Fire Line meter which comprises a meter inserted into the main wherein the meter includes a relatively large, weighted swing-arm valve which opens when pressure loss through the bypass meter approaches 4 psi. Connected in parallel with the relatively large valve is a domestic bypass meter having a relatively small swing-arm valve which responds to domestic consumption on the order of one gallon per minute or less. Disposed downstream of each valve is a register read by visual inspection.
It has been found that enormous quantities of water are dispensed without being billed for or accounted for due to deterioration of components of the swing-arm valves. This is usually due to the rubber seal adjacent the periphery of the valve being damaged by periodically closing on pebbles and other debris passing through the water main. These valves include a weight copivoted with the valve and a roller which rides on the weight. From time to time, the roller degrades or jams. This can also cause the valve to remain open, allowing quantities of water dispensed without being billed for.
Normally, Hersey Fire Line meters are contained in underground meter vaults which are entered through a standard twenty-two inch manhole cover and have a floor-to-ceiling height of approximately six feet. The mains to which the fire meters are attached are generally eight to twelve inches in diameter. Consequently, the valves are quite heavy as are the valve covers. For example, the weight of the valve cover on a Hersey ten-inch fire meter is approximately two hundred seventy-three pounds, the weight of the valve is approximately one hundred fifty-six pounds, while the weight itself is approximately ninety-six pounds. Handling equipment of this weight is difficult and hazardous for work crews, requiring two or three workmen to lift very heavy items in a confined space. Since these valves are difficult to maintain, water departments frequently let the valves leak which nationwide results in hundreds of millions of gallons of water being dispensed unmetered. This, of course, increases the price of water to users where the water is metered.
In view of these considerations, there is a need for apparatus specifically for handling valves and valve covers used in large water-metering equipment, such as the eight and twelve-inch Hersey Fire Line meters.